<!DOCTYPE html>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org"
      xmlns:c="http://www.w3.org/1999/html">
<head th:fragment="head" >
    <meta charset="UTF-8">
    <meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
    <!-- 项目开发阶段不需要缓存处理，但在实际项目上线使用后是需要缓存的，所以到时候注释掉下面代码即可 -->
    <meta http-equiv="Pragma" content="no-cache">
    <meta http-equiv="Cache-Control" content="no-cache">
    <meta http-equiv="Expires" content="0">
</head>
</html>